DAMASCUS, Syria - <FORM class=yqin action=http://yq.search.yahoo.com/search method=post> </FORM>Syria promised Friday to increase border patrols and work with Lebanese troops to thwart the flow of arms to its ally Hezbollah, but <FORM class=yqin action=http://yq.search.yahoo.com/search method=post> </FORM>Israel questioned whether the Damascus regime would be a "reliable force" in guarding the border.
If carried out, the promises made by Syrian President Bashar Assad to U.N. Secretary-General <FORM class=yqin action=http://yq.search.yahoo.com/search method=post> </FORM>Kofi Annan would be a major boost to efforts to keep the peace in Lebanon.
Preventing weapons from reaching Hezbollah is a key element of the U.N. resolution that halted Israeli-Hezbollah fighting Aug. 14. The truce also calls for a beefed-up U.N. force of 15,000 soldiers in southern Lebanon and more nations committed troops to the mission Friday.
The U.N. chief said that if Syria follows through in tightening control of the border, peace efforts will be greatly helped. "I have no reason to believe it will not be done," Annan said.
But Israel pointed to Syria's past role in allegedly supplying weapons to the Shiite guerrillas of Hezbollah and said it doubted Assad's regime had really changed its stance.
"Israel does not think that Syria ... has shown any reason to be a reliable force," said Miri Eisin, a spokeswoman for Israeli Prime Minister Ehud Olmert.
She said "numerous rockets and missiles made by Syria and supplied by Syria ... were fired against Israel" by Hezbollah during the 34-day Lebanon war.
Israel wants peacekeepers to also patrol Lebanon's border with Syria, but the U.N. truce does not give them the mandate to do so without permission from the Lebanese government. Israel has said it will not lift its punishing air and sea blockade of Lebanon until the U.N. moves onto the border.
Syria has said the deployment of U.N. troops along the border would be a "hostile" affront, and Annan said Assad repeated his opposition to it during their meeting.
While it remains to be borne out, Syria's vow to help implement the U.N. resolution was Annan's biggest diplomatic feat during an 11-day Mideast tour.
The U.N. chief had little success in Beirut, where Prime Minister Fuad Saniora said Lebanon would be the last Arab country to make peace with the Jewish state, and in Israel, where Olmert rebuffed Annan's call for quickly lifting the blockade of Lebanon.
Annan emerged from the meeting with Assad, saying the Syrian leader also expressed a willingness to establish diplomatic ties with Lebanon and demarcate the countries' border — a longtime demand of the U.N. and the Lebanese to affirm the end of Damascus' long domination of its neighbor.
Annan also said he asked Syria to "use its influence" to help win the release of three Israeli soldiers held by Hezbollah and militants linked to Palestinians allied with Damascus. Assad said he supported their release, but raised the plight of 16 Syrians detained by Israel in the occupied Golan Heights, Annan said.
Germany's intelligence chief, Ernst Uhrlau, who helped mediate a 2004 prisoner swap between Israel and Hezbollah, arrived in Beirut on Friday, but there was no immediate word on the nature of his mission, Lebanese officials said. There have been reports over the past week of behind-the-scenes mediation by European officials for another such swap.
Assad made no comment after his talks with Annan, and Syrian news reports about the meeting did not address the issues of stopping Hezbollah weapons or relations with Lebanon.
The U.N. chief expressed confidence Lebanese and Syrian troops could halt the flow of Hezbollah weapons over the border without the presence of U.N. peacekeepers.
"I think it can happen. It may not be 100 percent, but it will make quite a lot of difference if the (Syrian) government puts in place the measures the government has discussed with me," Annan said.

He said Syria agreed to boost the number of its own guards along the border, give them more training and establish joint patrols with Lebanese troops "where possible."
That would mark rare cooperation between Syria, whose troops pulled out of Lebanon last year after nearly three decades of domination, and Lebanon, where many people blame the 2005 assassination of former prime minister Rafik Hariri on Damascus.
The Security Council resolution calls on all countries to prevent the sale or supply of weapons to entities in Lebanon without the consent of the Lebanese government or U.N. peacekeepers. It also calls for Lebanon to "secure its borders and other entry points."
It is not the first time Syria promised to tighten its borders. The U.S. has accused Damascus of lax security on the Syria- <FORM class=yqin action=http://yq.search.yahoo.com/search method=post> </FORM>Iraq border, where Washington says insurgents have poured into Iraq. Syria vowed similarly to boost border patrols and work with U.S. officials, but insurgents are still believed to pass through.
Annan flies Saturday to <FORM class=yqin action=http://yq.search.yahoo.com/search method=post> </FORM>Iran, Hezbollah's other main backer and a country embroiled in its own fight with the West over the Iranian nuclear program.
Meanwhile, more progress was reported in assembling the U.N. force for southern Lebanon.
The Spanish government agreed Friday to contribute up to 1,100 soldiers, a step that parliament is expected to approve next week.
Israel dropped its objections to Indonesia joining the force, and the two sides were discussing when Jakarta would send 1,000 soldiers, a U.N. official said. Israel had opposed participation by states with which it doesn't have diplomatic relations.
Turkey's government submitted a resolution to its parliament for a vote Tuesday to send peacekeepers despite public opposition to the deployment.
A contingent of 800 Italian soldiers was due in the southern Lebanese city of Tyre on Saturday, the largest contingent to arrive so far to boost the 2,000-peacekeeper force that has been in southern Lebanon since 1978.
Armed with tanks, howitzers and other heavy weapons not normally used by peacekeeping forces, the U.N. troops will back up the Lebanese military, which has already begun moving into parts of the south as Israeli soldiers withdraw. The combined force is supposed to ensure Hezbollah does not openly have weapons in the area, although the U.N. force does not have a mandate to actively disarm the guerrillas.